1970s, Helium Dilution FRC, Spirometer Godart Pulmotest, 1974, Helium Dilution Lung Volume testing June 14, 2014 Richard Johnston Leave a comment From: Survey of Current Cardiovascular and Respiratory Examination Methods in Medical Selection and Control of Aircrew by A. Scano, NATO Agardograph No. 196, published December 1974, page 50.